1. Field of the Invention
This invention relates to a display device in a storage type image display device using a solid electron beam generating apparatus, and a display device in an electron ray generating apparatus using the solid electron beam generating apparatus.
2. Related Background Art
In recent years, the rapid advancement of image processing technique has increased the demand for devices for displaying images of great capacity. As a device for displaying such images of great capacity, there is known, for example, a storage type display device as shown in FIG. 5 of the accompanying drawings. In FIG. 5, reference numeral 11 designates a writing gun, and reference numeral 12 denotes a deflecting electrode. An electron ray emitted from the writing gun 11 is deflected by the deflecting electrode 12 in conformity with image information and arrives at a storage plate 15. The storage plate 15 comprises a thin film of a dielectric material formed on the surface of a fine metal mesh, and discharges secondary electrons and is charged positive when the electron ray impinges thereon. The amount of charges stored by charging corresponds to the image information. That is, the image information is preserved as an amount of positive charges. When this image information is to be displayed on a fluorescent screen 16, an electron ray is emitted from a flood electron gun 17 and applied to the whole surface of the storage plate 15 by a collimator lens 14. This electron ray passes through that portion of the storage plate 15 which has been positively charged, and is intercepted by the other portions. The electron ray having passed through this positively charged portion impinges on the fluorescent screen 16 and thus, the fluorescent material applied to the inside surface of the screen emits light. In FIG. 5, reference numeral 13 designates a collector electrode for catching the secondary electrons from the storage plate 15 and providing a return path.
In such a storage type display tube, however, it is necessary to provide discrete electronic optical systems in the writing electron gun and the applying electron gun, respectively, and this has led to the structural complexity and bulkiness of the tube, which has also led to a high manufacturing cost.
Also, the flood electron gun 17 is designed to apply an electron ray to the whole surface of the storage plate 15 and therefore partial erasing is not possible, and this has led to the inconvenience that even when only a part of the displayed image is to be rewritten, the whole screen must be once erased.
On the other hand, for example, in the fields of recording and electron ray lithography, various devices have heretofore been proposed as applications of electron ray lithography. However, these devices use chiefly hot cathodes as electron ray sources. The hot cathodes used in these devices utilize the hot electron emission by heating and therefore have suffered from the disadvantage that they require high power consumption and moreover a certain degree of pre-heating time and cannot be immediately operated when the power source is switched on. Also, where image display is effected by the use of an electron ray, to achieve a great capacity and a high speed it will be advantageous to dispose a plurality of electron ray sources, but it has been difficult to arrange conventional hot cathodes of uniform characteristics with high positional accuracy.